Metal casting



Oct. 15, 1935, J. J. BOAX METAL CASTING Filed April 16, 1954 2Sheets-Sheet 1 ziwenfar JoH/v J. 504x, 5% M Patented Oct. 15, 1935PATENT OFFICE METAL CASTING John 1. Boat, McKeesport, Pa., asaignor toNational Tube Company, a corporation of New Jersey Application April is,1934, Serial No. 720,869

1 Claim. I (01. 22-19) This invention relates to apparatus for castingmolten metal, particularly molten steel, one of the objects being toobtain better castings. Other objects may be inferred. Referring to thedrawings:

Figure 1 is a sectional view showing a steel ladle, a tundish-and aningot mold, the last element being of reduced size to conserve space inthe illustration.

1 I Figure 2 is an enlarged top view of the nozzle in the tundish.

Figure 3 is a longitudinal cross-section of a different kind of nozzlewhich may be used in the tundish.

Figure 4 is an elevation looking in the direction of the arrows IV-IV inFigure 3. Flgm'e 5 is a top portion of this nozzle looking in thedirection of the arrows V-V in Figure 4.

Figure 6 is a top view looking down in the direction of the arrows VI-VIin Figure 5.

' A conventional teeming ladle l is arranged over a tundish 2 beneathwhich an ingot mold 3 is positioned. The molten metal is teemed from theladle I into the tundish 2 from which it is in turn teemed into theingotmold 3.

The nozzle 4 of the tundish: 2 is characterized in that it consists of arefractory body through which a plurality of parallel passages i extendvfrom end to end. These passages Ii are adjacently grouped and one endof the body is shaped to provide a concave face 8 which cooperates witha stopper of suihcient size to close all of the adjacent openings to thepassages 5. This stopper may be of the usual type consisting of a bar 8surrounded by a refractory 8 and having a graphite tip ll.

Among ingot defects are blow-holes formed by included gases and surfaceslivers caused by metal which has splashed onto the side of the U moldduring pouring.

The apparatus described converts the solid heavy stream coming from theteeming ladle I into a number of small lazy streams flowing into theingot mold. This permits escape of some of the included gases anddecreases splashing of the 1 metal as it strikes the bottom of the mold.These advantages are particularly apparent if the casting is carried outin vacuum.

In the other illustrated arrangement, the tundish 2 is provided with adiflerent teeming nozzle that consists of a refractory body ll shapedfor insertion in the nozzle opening of the tundish and in whichaplurality of parallel passages l2 5 are formed. The top of this body isshaped so that the portions l3 surrounding the passages l2 extendupwardly to different heights. By this means the metal may be teemed involumes varying acm cording to the amount of metal in the tundish. Theportions II should be arranged so that rising metal in the tundish 2will flow through one after another of the passages l2. 4

Referring more specifically to this variable volume nozzle, the portionsii of the refractory body I I are arranged so that there is a centralupstanding one I! surrounding a central relatively large passage ii. Asecond portion ll concentrically the tundish at various heights. Thesepassages 25 may be somewhat smaller than the central one. Although aspeciflcexample of the inventionds described in accordance with thepatent statutes,

it is not intended to limit the scope of theinven- 30 tion exactlythereto, except as defined by the,

following claim.

I claim:

' A teeming nozzle for molten metal, including a refractory body shapedfor insertion in the nozzle opening of a tundish and having a topconstructed to provide a central upstanding portion through which apassage is formed, and a second portion that concentrically surroundssaid central portion and which has a sloping top edge that spiralsdownwardly around the same, other passages being formed through saidbody parallel to the first named passages so as to open into the topedge of said second portion at spaced positions, all of 'said passagesbeing straight and opening through thebottom of said body.

. JOHN J. BOAX.

